Actinic radiation protection by compositions comprising quinones and carbonyl containing compounds



United States Patent ACTINIC RADIATION PROTECTION BY COMPO- SITIONS COMPRISING QUINONES AND CAR- BONYL CONTAINING COMPOUNDS Walter J. Runge, St. Paul, Minn., assignor to The Regents of the University of Minnesota, Minneapolis, Minn., a corporation of Minnesota No Drawing. Filed June 15, 1962, Ser. No. 202,674

16 Claims. (Cl. 167-90) 7 This application is a continuation-in-part of Serial No. 126,899 filed on July 26, 1961, which is now abandoned.

This invention relates to a material and method useful primarily for shielding the human skin from light to protect the skin from the effects of actinic radiations such as sunlight and the like of wavelengths between about 2900 and 26,850 angstroms. The skin of virtually all persons is sensitive to sunlight to some degree. Many people are extremely sensitive to the extent that they must severely restrict or control their exposure to bright sunlight. The present invention affords a simple and effective means for protecting all persons from the painful effects of overexposure to sunlight. To persons of extreme light sensitivity, the present invention offers a means toward nearnormal livelihood.

Broadly stated, the light shield producing material of the present invention comprises a mixture of a benzoor naphtho-qninone, and more particularly alpha and beta tautomers of benzoand naphth-o-quinones and their derivatives capable of 1,4 additions, in compatible solution with carbonyl containing compounds which are reactive with amino derivatives of protein to form melanoidins and applied to the skin, as a lotion or admixed in a cream base. Exemplary operable quinones include juglone. (5-(8)-hydroxy-1,4-naphthoquinone; C H O menadione (2-methyl-1,4-naphtl1oquinone, C H O henna (Z-hydroxy-l,4-naphthoqninone); 2,6-dimethoxy benzoquinone;

2,5-dimethylquinone; 2,5-dihydroxy-3-undecyl-1,4-benzoquinone; 2-hydroxy-3-methyl-1,4-naph-thoquinone;

3,5 ,S-trihydroxy-Z-methyl-1,4-naphthoquinone and 2-hydroxy-3-isobutyl-1,4-naphthoquinone.

For aesthetic reasons crystalline juglone is a preferred material and for convenience the invention will be described with specific reference to juglone. The invention, however, is not limited to use of juglone. The statements made with respect to juglone are applicable to the other quinones. The quinones may be used singly or in admixture with one another.

Exemplary operable carbonyl compounds include dihydroxyacetone (DHA); S-(hydroxymethyl)-2-furaldehyde (HMF); pyruvic aldehyde; glyceraldehyde; alloxan and monohydroxyacetone (Acetol). These compounds are all reactive with amino derivatives of protein, as present in the human skin, to form melanoidins. They are readily polymerizable. They are tolerable to the skin in that upon application they do not normally cause undue discomfort arising from erythema, itching, burning, etc. For convenience the invention will be described with particular reference to dihydroxyacetone. The invention, however, is not so limited. The carbonyl containing compounds may be used singly or in admixture with one another.

Jnglone by itself is known to produce colored reaction products with skin and keratin and is used as a hair coloring agent. Dihydroxyacetone by itself is also known to produce a tan color in certain organic materials and is the main constituent of commercial artificial suntan lotions. (U.S. Patent No; 2,949,403.) Neither juglone alone nor dihydroxyacetone alone has any appreciable protective effect against actinic burns.

The combination of a quinone and carbonyl containing compound in a suitable solvent does not produce a mere additive effect. As evidence of this, juglone by itself is an effective coloring agent for skin, but the coloration of skin with juglone can be inhibited by mercurous chloride. Similarly, the pigmentation of skin by dihydroxyacetone can be blocked completely with formaldehyde. The tanning of skin by the mixture of juglone and dihydroxyacetone, however, is not blocked by mercurous chloride and formaldehyde.

Wide variations in concentration of the ingredients comprising the protective material are possible. The quinone may be present in the final solution in concentration from about 0.001% to saturation and the carbonyl containing compound may be present in concentrations from about 1% to saturation. In the case of dilute preparations, more frequent application to the skin is necessary to produce and maintain the desired protective effect. The light shield producing material may be prepared in any compatible non-irritating solvent which is capable of maintaining both compounds in solution. Juglone is slightly soluble in hot water, freely soluble in chloroform and benzene, soluble in methanol, ethanol and other alcohols, in acetone and ether and the like. Dihydroxyacetone is soluble in water, alcohols, ketones such as acetone, and ethers, etc. Exemplary solvents capable of maintaining both compounds in solution include C through C alcohols ranging from dilute alcohols to absolute, ethers, acetone, glycerin, water, etc.

The final solution may have a pH ranging from acid to slightly above neutral. The effectiveness of the light shield producing material is independent of pH but the material becomes less stable above pH 7.2. Preferably, the solution pH range is between about 4.2 and 5, which approximates the normal pH of skin.

The quinone and carbonyl containing compound are preferably first separately dissolved and then admixed. Where the final solution includes a water-containing alcohol, the solution should desirably be stored in a cool dark place for about five days before use in order to give color stability to the product. This is due to complexing of some quinones in Water-containing alcohols which causes a color change.

The quinone and carbonyl containing compound may be present in the relative proportions of between about 0.05: and 202100 and preferably in the proportions of about 0.5 to 10 parts quinone to each 100 parts of carbonyl containing compound. The optimum proportion to produce the desired effect on human skin is about 1:100. The combined solution of the quinone and carbonyl containing compound may be applied directly to the skin as a lotion or it may be admixed with a hydrophilic cream base and applied as a cream or ointment. Nonoxidizing or reducing compounds, such as vitamins or hormones or the like, may be admixed without adverse efiect upon the light shielding reaction of the materials with the skin.

The lotion is painted or sprayed or rubbed on the areas to be protected. Preferably, from about .3 to 6 coatings, applied at least 45 minutes apart, are used and desirably the protection is renewed every other day in the evening by the application of an additional coating. The light shield producing material functions by reacting with the skin surface. In order to allow time for the action to proceed, the skin should not be washed for at least 1 /2 hours after application of the protective solution.

When the shielding material is prepared as a cream, any of the common readily available proprietary toilet or cosmetic or medicinal cream bases, including synthetic cream bases, may be used so long as they emulgate the solutions of quinone and carbonyl containing compound in the selected solvents. The protective cream or ointment is rubbed in thoroughly one or more times daily in order to permit the reaction to proceed at the skin surface. Water should not be applied for at least two hours after application.

Although the manner in which the reactions with the skin occur and protection is imparted to the skin surface is not fully understood, it is known that the reaction involves sulphur-hydrogen groups present in the cornified layer of skin. It is believed that the intense ultraviolet absorption of the reaction product between the skin and the protective solution may be related tolthe occurrence of sulphur addition to the naphthoquinone ring, probably in positions 2 and 3. The color reaction of the solution of a quinone and carbonyl containing compound with the skin may be intensified by pretreating the skin with a substance, such as solutions of thioglycolic acid and its salts, which functions to free sulphur-to-sulphur bonds in the skin to produce larger numbers of sulphur-hydrogen groups in the skin. The same effect may be obtained by incorporating the color intensifying material directly in the protective light shield producing material.

The application of the juglone-dihydroxyacetone containing mixture to the skin produces a brown, yellow tan resembling normal suntan. This color reaction creates an effective epidermal optical filter which, as part of the skin itself, cannot be removed easily by water, washing with soap, and mild mechanical abrasion. The solvent evaporates to leave a thin oily film to react with the skin.

The spectral transmission characteristics of the color layer produced by reaction of the juglone-dihydroxyacetone mixture are significantly different from coloration obtained by either juglone or dihydroxyacetone alone, as studied by absorption measurements by spectrophotometric means of the cornified layer of skin after application of the compounds. The spectral transmission of the skin colorations is furthermore quite diiferent from the transmission of the juglone-dihydroxyacetone mixture in solution, and either compound alone in solution.

The percentage of light transmitted through a cornified layer of skin treated respectively with a juglone-dihydroxyacetone solution and solutions of both compounds alone as compared with untreated skin is shown in Table I. The table illustrates that 'within the sunburn spectral range (2900 A. to 3200 A.) the light transmission of skin colored by reaction with juglone-dihydroxyacetone solution is less than of the avail-able energy. For example, at 3000 A. the normal untreated skin layer transmitted 75% of the light; that treated with dihydroxyacetone solution transmitted 58%; and that treated with juglone solution transmitted 70% of the available light. In contrast, the transmission of light through the skin treated with the juglone-dihydroxyacetone combined solution was only 1%.

TABLE I.TRANSMISSION OF LIGHT IN PERCENT luglone treatment only the treatment of combined solution and dihydroxyacetone alone.

2 Values obtained as T 26,850100%.

5 Values obtained as T 3,600100%.

A washable light shield producing material may be produced by reacting a solution of a quinone and carbonyl c-ontaining compound solution with a sulphur containing amino acid or sulphydryl-containing compound or certain basic amino acids prior to application of the solution to the skin. Exemplary additive materials include glutathione, cystine, cysteine, methionine and arginine. When these materials are used, the color reaction takes place between the solution of quinone and carbonyl containing compound and the sulphur-containing compound before application of the material to the skin. This resulting brownish colored product is applied to the skin in the form of a cream or lotion. While it gives protection against ultraviolet light, it is removable with water, soap, mild organic solvents and abrasion, but may be used where more long lasting coloration of the skin is not desired.

The preparation and composition of the protective light shield producing materials of the present invention are further illustrated by the following examples.

Example 1 A protective lotion is prepared by dissolving 0.35 part by weight of chemically pure grade crystalline juglone in 156 parts \by weight (200 parts by volume) of absolute isopropanol heated to a boil. After cooling, this solution is mixed in a brown bottle with a solution of 30 parts by weight of dihydroxyacetone (C.P.; melting point 81- 82 C.) in 300 parts by weight of distilled water and 394 parts by weight (500 parts by volume) of absolute isopropanol. The volume is restored to 1,000 parts by addition of isopropanol. The ingredients are thoroughly admixed to insure solution. The mixture is then set aside for five days until it becomes color stable. The pH is adjusted to between 4.2 to 4.9 by addition of acetic acid. The final concentration of the lotion is juglone 0.035% and dihydroxyacetone 3%, in isopropanol 70% (by volume). Wm W' n Example 2 A cream light shield producing material is prepared by dissolving 0.35 part by weight of juglone in 200 parts by weight (250 parts by volume) of absolute ethyl alcohol. A second solution composed of 30 parts by weight of dihydroxyacetone in 250 parts by weight of distilled water is prepared and emulgated with 500 parts of weight of Aquaphor, a proprietary hydrophilic cream base. The previously prepared juglone solution is added and the mixture is once more emulgated thoroughly. It is stored in a cool, dark place and is ready for application after five days. The final concentration of the cream preparation is juglone 0.035%, dihydroxyacetone 3%, ethanol 50% (by volume) and cream base 50%.

Examples 3 to 20 The following examples illustrate varying proportions ofjuglone relative to dihydroxyacetone and varying concentrations of these materials in various solvents. Each of these exemplary solutions is applied to the skin as a lotion. In each instance, juglone and dihydroxyacetone are shown in grams per liter. of solution. The proportions of solvent are shown in volume percentages. In each instance, the solvent was compatible to maintain both the juglone and the dihydroxyacetone in solution. The examples are summarized in the table:

TABLE II Example .Tuglone Dihydroxy- .Tuglone/ Volume, No. (Grams/Liter) acetone DHA Solvent Percent (Grams/Liter) Ratio 3 4 40 101100 {ff i8 4 0. 01 20 0. 03100 8 5 4 40 10=10o 0. 01 20 0. 05100 g8 7 3o 10.7;100 38 s 0. 2 300 0. 007:100 9 4 40 101100 10 0.3 30 1:100 50 11 1 40 2.51100 30 50 12 0.3 30 1:100 30 20 30 13 0. 4 1. 01100 23 14 0.3 11100 W t t 100 a B1 S3. ura e 15 0.6 30 2.100 {Ethylmhern 100 Ethyl Ether 20 16 0.9 1.8:100 Isopropanol. 10 Water 70 Aoetone 10 17 0. 35 30 1.171100 Impropa g 5 1s 0. 7 100 0. 71100 55 40 10 10 0. 5 15 3. 3100 2 20 ,0. 3 43 0. 00=100 s4 10 Examples 21 to 25 The following examples illustrate various cream or ointment protective preparations. In each instance the juglone was dissolved in either absolute ethanol or isopropanol in the stated proportion and the dihydroxyacetone was dissolved in distilled water in the proportion shown. The ointment was prepared by generally following the procedures of Example 2. Proprietary hydrophi'lic ointment bases were used. The results are summarized in the table:

45 dissolved in water.

reacting the juglone-dihydroxyacetone solution with a sulphur containing amino acid or sulphydryl containing 40 compound in solution and emulgating with a cream base to form an ointment. In each instance, the sulphur compound was dissolved in water, the juglone was dissolved in absolute ethanol and the dihydroxyacetone was The ratio of juglone to dihydroxyacetone was 1.17 in each instance. The examples are summarized in the table.

Polyethylene Glycol 1540,

TABLE IV Sulphur Compound Juglone Dihydroxy- Example (Grams/Liter (Grams/ Liter acetone Ointment No. of Solvent) of Solvent) (Grams/Liter (2 Kilograms) of Solvent) Glutathione-36 1. 4 Aquaphor. CyStine-20 l. 4 120 Multibase." d o 1.4 120 Plastibase.

Metl11onine-20 1. 4 120 Hydrosorb Examples 26 to 29 A washable light shield producing ointment was pre- Examples 30 to 46 The effectiveness of the light shielding material acpared according to each of the following examples by 75 cording to the present invention was tested upon a group of seventeen persons selected for known sunburn sensitivity. The inside forearm of each person was exposed to radiation of unfiltered light from a hot quartz lamp at a distance of 22 inches for a given number of minimal erythemal doses (MEDs), each consisting of exposure Examples 47-53 To further test the effectiveness of the light shielding material according to the present invention a number of patients with known diseases with light sensitivity factor 5 were treated with the preparations of Examples 1 and 2, for 15 F P Certam areas of the skm were Protect; both in lotion and in ointment form. These examples b l atio about 16 to 18 hours before E P f are summarized in Table VI which is a summary of the the 10mm of Exemple For eempanson er areas clinical diagnoses, the length of time the disease was the forearm i Were left untreited' e E gag present before treatment, the time the patient was treated area? of the km were exposed to e S with the protective material of this invention, the pro- Fequlred to Produce redness P number mdleated tection afforded by this material and the occurrence of column 4 of Table As an lnustranon m Exafnple previous failures with other sun protection agents.

30, the untreated skin area was sub ected to 4 MED s, or In the instances of Examples 47, 50 51 and 52 the atotalexpesure of 60 seeonds' b patients were treated alternately with both a protective e i i areas were expesedb to the g of lotion and a protective ointment. -In the cases of Ex- M mdleated column 5 Ta 1e V to t e pro amples 48 and 49, the initial treatment was by applicaof rednessw tion of the lotion of Example 1 by sprayingand sub- Where an astel'lsk (T) follows the number of MED S sequently by application of the ointment of Example 2. 0011111111 4 of column 5 the GXPOSUW treatment Was Stopped In the instance of Example 53 the treatment was by ointat t s n r of MEDS Wlth I10 pp redness merit only. The protection afforded is cumulative and iIlg been P Thus, 111 the Case Of EXaIIIPIB increases with length of treatment. All of these patients four MEDs produced redness of the untreated skin, are extremely sensitive to exposure to sunlight.

TABLE VI Length of Percent Previous Example Time of Trcatimprovement Protection No. Age Sex Diagnosis Diagnosis ment of percent by sun before Trcat- Time protection screen ment, yrs. agents M Sunlight sensitivity 10 1 mo. 95 All failed. 40 M ....de 4 3wks.-- 100 Do. 72 F Discoid Lupus Erythe- 17 2wks... Do.

matosus. F Eczema with sunlight 15 3mos.-. Do.

sensitivity. 24 F Ptrptliiyria eutanca 2 3mos.-- 100 Do.

ill 3.. 14 F Erythropoetic por- 14 3mos... 100 D0.

phyria congenital. 27 F Eczema with sunlight 2 1wk 50 None tried.

sensitivity.

but three times this exposure of the treated skin produced no redness and the exposure was stopped. One minimal erythemal dose (MED) is the equivalent of approximately 24 to 36 minutes exposure to direct sunlight at high noon on a summer day. In each instance, the tolerance of the person to exposure to direct sunlight was significantly increased as a result of treatment of the skin with the light shielding material according to the present invention. The results of these test exposures are summarized in the table:

As a test of the possible toxicity of the protective material of this invention, 100 milliliters of a solution prepared according to Example 1 except that ethanol was used as the solvent, was ingested by a normal adult male. No ill effects were noted immediately after ingestion or after a prolonged period of time. Two normal individuals, one male and the other female, have applied the protective preparations to their skin over prolonged periods of time without developing any primary irritant or allergic reactions.

TABLE V Erythema after actual MEDs on inside forearm Exlarmple Sex Hair Untreated Treated Diagnosis F 4 9 Ectopic eczema with light sens. M 4 10* Normal. M 2 8 Do. M 6* 10* Light sensitivity to LR. M 2 10 Normal. F 1 6 Do. F 4 10* Do. F 4 10* Do. F 2 4 Pregnancy, normal. M 2 10 Normal. M 2 10* Porphyria cutanea tarda. F 1. 5 10* Normal. F 2 10* D0. F 2 10* Do. M 1 10* Light sensitivity. F do 4 10* Lupus Erythematosus. F D. bl0nde 4 12* Normal.

9 Examples 54 to 56 In order to evaluate the effectiveness of other quinones, preparations were made generally according to the procedures of Example 1, as follows:

What is claimed is:

1. A light shield producing material for the protection of human skin from actinic radiation of wave length between about 2900 and 26,850 angstroms which comprises In each instance, the preparation was applied to skin and exposed to actinic rays and, in each instance, effective protection to the skin was afforded. The color of the skin after application of these preparations, however, was less pleasing than that resulting from juglone-containing preparations. For this reason juglone is a preferred material.

Examples 57 to 68 Other light shield producing materials utilizing other carbonyl containing compounds are made generally ac cording to the procedures of Example 1, as follows:

a dissolved mixture of a quinone selected from the class consisting of alpha and beta tautomers of 1,4-benzoand 1,4-naphtho-quinones and a carbonyl containing compound selected from the class consisting of dihydroxyacetone, 5-(hydroxymethyl)-2 furaldehyde, pyruvic aldehyde, glyceraldehyde, alloxan and monohydroxyacetone, said quinone and carbonyl containing compound being dissolved in a mutual non-irritating organic solvent.

2. A light shield producing material according to claim 1 further characterized in that said quinone and carbonyl containing compound are present in proportions between about 0.05: 100 and 20:100.

compound to the skin is that the mixture functions as a skin antiseptic. It functions as a bactericide or bacteriostat fixed to the skin. In this role it is useful in preparation of anatomic areas for surgery. When used in open skin sores and infected lesions and on 'burns the material promotes healing.

For convenience, the source of each of the exemplary proprietary cream bases is given below:

TABLE IX AquaphorDuke Laboratories, South Norwalk, Conn. M ultibase-Ar-Ex Products Co., Chicago 7, 1-11. PlastibaseE. R. Squibb & Sons, New York, N.Y. Hydrosorb-Abbott Laboratories, North Chicago, Ill.

It is apparent that many modifications and variations of this invention as herein'before set forth may be made without departing from the spirit and scope thereof. The specific embodiments described are given by way of example only and the invention is limited only by the terms of the appended claims.

TABLE VIII Example Quinone (Grams/ Carbonyl Compound Solvent Volume, No. Liter) (Grams/Liter) Percent v 57 Henna, 0.35 HMF, 3o g8 '58 do Pyruvic aldehyde, t 01 40 59 do Glyceraldehyde, 30 Ethyl Ether-- 40 Water 20 Menadione, 0.35 Acetol, 30 z agg fg i j g8 Menadione, 4 HMF, 40 J'uglone, 0.3 Aceto1,30 ea "do HMF, 30 40 8-hydroxy-1,4-naph- 64 thoquinone, (L Glyceraldehyde, 30 65 Menadione, 0.35 Pyruvic aldehyde, 30.. so Juglone, 0.30 Alloxan, so 3o 67 Henna, 0.35.. {A 30 Water 68 Menadione, 0.30 do {ggggfjifl- I gg A beneficial side eifect observed as the result of applica- 3. A light shield producing material according to claim tion of solutions of a quinone and a carbonyl containing 1 further characterized in that said quinone is present in concentration between about 0.001% to saturation and said carbonyl containing compound is present in concentration between about 1% and saturation.

4. A light shield producing material according to claim 1 further characterized in that said material is in the form of an ointment, said dissolved mixture being emulgated in acream base.

5. A light shield producing material for the protection of human skin from actinic radiation of wave length between about 2900 and 26,850 angstroms which comprises a dissolved mixture of a quinone selected from the group consisting of henna, menadione and juglone, and dihydroxyacetone, said quinone and dihydroxyacetone being dissolved in a mutual non-irritating organic solvent.

-6. A light shield producing material for the protection of human skin from actinic burns from radiations of wave length between about 2900 and 26,850 angstroms which comprises a dissolved mixture of a quinone selected from the class consisting of henna, men-adione and juglone and dihydroxyacetone in a mutual non-irritating solvent, said 1 1 quinone and dihydroxyacetone being present in proportions between about 0.05 :100 and 20:100, said quinone being present in concentration between about 0.001% to saturation and said dihydroxyacetone 'being present in concentration between about 1% and saturation.

7. A light shield producing material according to claim 6 further characterized in that said material is in the form of an ointment, said dissolved mixture being emulgated in a cream base.

8. A method for protecting human skin from actinic radiation of wave length between about 2900 and 26,850 angstroms which comprises applying to the skin a dis solved mixture of a quinone selected from the class consisting of alpha and beta tautomers of 1,4-benzoand 1,4-naphtho-quinones and a carbonyl containing compound selected from the class consisting of dihydroxyacetone, -(hydroxymethyl)-2-furaldehyde, pyruvic aldehyde, glyceraldehyde, alloxan and monohydroxyacetone, said quinone and carbonyl containing compound being dissolved in a mutual non-irritating organic solvent.

9. A method according to claim 8 further characterized in that said quinone and carbonyl containing compound are present in said material in proportions between about 0.05: 100 and 20:100.

10. A method according to claim 8 further characterized in that said quinone is present in concentration in said material between about 0.001% to saturation and said carbonyl containing compound is present in said material in concentration between about 1% and saturation.

11. A method according to claim 8 further characterized in that said material is applied to the skin as a solution in a plurality of at least three coatings, applied at least forty-five minutes apart, and renewed by periodic reapplications.

12. A method according to claim 8 further characterized in that said material is applied in the form of an ointment, said dissolved mixture being emulgated in a cream base.

13. A method of providing temporary protection for the protection of the human skin from radiation burns caused by radiations of wave length between about 2900 and 26,850 angstroms which comprises applying to the skin a dissolved mixture of a quinone selected from the class consisting of henna, menadione and juglone and dihydroxyacetone in a mutual non-irritating solvent.

14. A method of protecting human skin from radiation burns caused by radiations of wave length between about 2900 and 26,850 angstroms which comprises applying to the surface of the skin a dissolved mixture of a quinone selected from the class consisting of henna, menadione and juglone and dihydroxyacetone in a mutual non-irritating solvent, said quinone and dihydroxyacetone being present in proportions between about 0.05 :100 and 20:100, said quinone being present in said material in concentration between about 0.001% to saturation and said dihydroxyacetone 'being present in said material in concentration between about 1% and saturation, said material having a pH between about 4.2 and 5; applying said material to the skin in a plurality of at least three coatings applied at least forty-five minutes apart and maintaining said prottleiction by periodic reapplication of said material to the s 111.

15. A light shield producing material for the protection of human skin from actinic radiation of wave length between about 2900 and 26,850 angstroms which comprises a dissolved mixture of a quinone selected from the class consisting of juglone, menadione, henna, 2,6-dimethoxy benzoquinone, 2,5-dimethylquinone, 2,5-dihydroxy-3-undecyl-1,4-benzoquinone, 2-hydr0xy-3-methyl- 1,4-naphthoquinone, 3,5,8-trihydroxy-2-methyl-1,4-naphthoquinone and 2-hydroxy-3-isobutyl-1,4-naphthoquinone and a carbonyl containing compound selected from the class consisting of dihydroxyacetone, 5-(hydroxymethyl)- 2-furaldehyde, pyruvic aldehyde, glyceraldehyde, alloxan and monohydroxyacetone, said quinone and carbonyl containing compound being dissolved in a mutual non-irritating organic solvent.

16. A method for protecting human skin from actinic radiation of wave length between about 2900 and 26,850 angstroms which comprises applying to the skin a dissolved mixture of a quinone selected from the class consisting of juglone, menadione, henna, 2,6-dimethoxy benzoquinone, 2,5-dimethylquinone, 2,5-dihydroxy-3-undecyl-l,4-benzoquinone, 2-hydroxy-3-methyl-1,4-naphthoquinone, 3,5,8-trihydroxy-2-methyl 1,4 naphthoquinone and 2-hydroxy-3-isobutyl-l,4-naphthoquinone and a carbonyl containing compound selected from the class consisting of dihydroxy-acetone, 5- (hydroxymethyl)-2-furaldehyde, pyruvic aldehyde, glyceraldehyde, alloxan and monohydroxyacetone, said quinone and carbonyl containing compound being dissolved in a mutual non-irritating organic solvent.

References Cited by the Examiner Goldman, J. Soc. Cos. Chemists 12:3, April 1961, pp. 163-167.

Maibach, Arch of Derm., vol. 82, 1960, pp. 73-505 75-507.

JULIAN S. LEVITT, Primary Examiner. FRANK CACCIAPAGLIA, Examiner.

ANNA P. FAGELSON, VERA C. CLARKE,

Assistant Examiners. 

8. A METHOD FOR PROTECTING HUMAN SKIN FROM ACTINIC RADIATION OF WAVE LENGTH BETWEEN ABOUT 2900 AND 26,850 ANGSTROMS WHICH COMPRISES APPLYING TO THE SKIN A DISSOLVED MIXTURE OF QUINONE SELECTED FROM THE CLASS CONSISTING OF ALPHA AND BETA TAUTOMERS OF 1,4-BENZO- AND 1,4-NAPHYTHO-QUINONES AND A CARBONYL CONTAINING COMPOUND SELECTED FROM THE CLASS CONSISTING OF DIHYXDROXYACETONE, 5-(HYDROXYMETHYL)-2-FURALDEHYDE, PYUVID ALDEHYDE, GLYCERALDEHYDE, ALLOXAN AND MONOHYDROXYACETONE, SAID QUINONE AND CARBONYL CONTAINING COMPOUND BEING DISSOLVED IN A MUTUAL NON-IRRITATING ORGANIC SOLVENT. 